Coulier or draw mechanism of straight bar knitting machines



Feb. 8, 1955 K. w. WlcKARDT coULIER 0R DRAW MECHANISM oF STRAIGHT BAR KNITTING MACHINES Filed Sept. 25, 1950 Kw2 r w11. 1./ #wc/ 4190 r [n venior A Horn United States Patent O COULIER R DRAW MECHANISM 0F STRAIGHT BAR KN ITT ING MACHINES Kurt Willi Wickardt, Liverpool, England, assignor to Hoscmaster Machine Company Limited, Liverpool, England, a British company Application September 23, 1950, Serial No. 186,372

7 Claims. (Cl. 66-110) The present invention relates to the coulier or draw mechanism of straight bar knitting machines, and is especially applicable to machines of the Cotton type adapted for the production of full fashioned stockings.

The welt and the leg panel of the stocking blank are usually worked at a high normal working speed up to the beginning of the high heel. From the start of the high heel, however, when parts of the hose are spliced by an extra thread, which is worked in addition to the ground thread, the speed of the thread carriers and the slurcocks has to be decreased, in order to obtain satisfactory working. The reduction of these speeds is commonly obtained by reducing the speed of the machine, which at the same time reduces the working speed and so descreases the production of the machine.

lt is the object of the present invention to provide means for reducing the speed of the thread carriers and the slurcocks from the commencement of the high heel or from another suitable point, while maintaining the speed of the machine and consequently the production s eed.

I)On full fashioned hose machines the thread is laid on the sinker neb during one part of the time period available for the working of each row of loops-chiefly during the first part of this periodand the loops are drawn. Then in the second part, the drawn loops are worked into stitches. When drawing the loops in the normally known design of straight bar knitting machines the slurcock must always move over the full width of section, for example, even when the width of fabric has been reduced by narrowing to, for example, 9" at the beginning of the high heel, or adjusted to, for example, l0" at the beginning of the foot. lf the amplitude of travel of the slurcock were shortened for the narrower fabric, the speed of the slurcock could be decreased to correspond to the shorter amplitude without reducing the working speed of the machine and, consequently, the speed of production.

According to one feature of the present invention in the knitting of fabrics of varying width the speed of part of the knitting cycle during the knitting of narrower courses is reduced without increasing the time taken to complete the cycle.

According to another feature of the present invention in the knitting of fabrics of varying width the thread laying speed is reduced during the knitting of narrower courses without reducing the number of courses knit per unit time.

According to a still further feature of the present invention a straight bar knitting machine is provided with a draw mechanism including at least two draw cams affording different amplitudes of linear movement to the draw mechanism.

The invention will be further described by way of exarlipllc: with reference to the accompanying drawings in w lc Fig. l is a perspective view of one embodiment of the invention.

Fig. 2 is a sectional elevation of one arrangement for operating the central section only of the jack sinkers whilst the slurcock is within the section and Fig. 3 is a front elevation of an alternative arrangement of operating the central section only of the jack sinkers whilst the slurcock is traversing less than the full width of the jack head.

In Fig. l, a shaft l, rotatably mounted in the frame of the machine at right angles to cam shaft 2 is driven lCC by the cam shaft 2 of the machine by a pair of bevel wheels 3. The shaft 1 carries two draw cams 4 and 5 fastened to it, these cams being so shaped that cam 4 brings about movement of the slurcock over the whole width of knitting section, while cam 5 brings about movement of the slurcock only over that part which is adequate for the necessary width of fabric at the commencement of the foot of the hose. Two rollers 6, 7 are rotatably and slidably mounted on stud shafts 8 and 9 projecting from a bar 10 which is linearly displaceable in brackets 11 and 12 and which serve to cause the bar 10 to move to right and left horizontally with each complete revolution of the cams 4 and 5. As will be hereinafter described the rollers 6 and 7 are brought into operative engagement with cam 4 or with cam 5 as required so that a reciprocating motion of selected amplitude is imparted to the bar 10 and this reciprocation is transmitted at least to the slurcocks in any known manner.

One method of bringing the rollers 6, 7 into engagement with the required cam 4 or 5 is shown in Fig. l. The rollers 6, 7 are slidably mounted on stud shafts 8, 9 and are movable thereon by frame member 13 which is slidably carried in slots in bar 10. A portion 14 of the frame 13 extending substantially parallel to the axis of bar 10 and on the opposite side thereof to the rollers 6, 7, is slidably carried in the forked upper ends 15, 16 of levers 17, 18 which are keyed to shaft 19. A control lever 20 also keyed to shaft 19 is connected by link 21 to the lever 22 which is resiliently urged into its forward position by means of spring 23 so that, in the absence of any additional applied force, the rollers 6, 7 are urged into a position in which they are in contact with cam 4.

The lever 22 on its outer end carries a pin 24 upon which is mounted cam follower 25 adapted to be brought into and out of engagement with cam 26 keyed to cam shaft 2. Movement of cam follower 25 axially of pin 24 is etected by guide 27 one end of which bears on a grooved portion of the cam follower 25, the other end of the guide 27 being slidably mounted on a second control rod 28.

Control chain 29 carries in known manner at appropriate points one or more studs 30 adapted to engage one arm of bell crank lever 31, the other arm of which is in engagement with first control rod 32 which is slidably mounted in bearings 33, 34. The control rod 32 is normally urged to the left, that is to say, into contact with bell crank lever 31, by means of compression spring 35 disposed between bearing 33 and a collar 36. Control rod 32 carries contact block 37 co-operating with contact block 38 on the second control rod 28 so that movement of control rod 32 to the right will cause movement of control rod 28 also to the right by means of compression spring 39 disposed between bearing block 34 and collar 40. Control rod 28 is normally urged so that contact blocks 38 and 37 abut. By means of compression spring 42 located between the end of guide 27 and a further collar 43 guide 27 is normally urged into abutment with collar 41. Also slidably mounted on control rod 32 is one end of locking lever 44 which is normally urged into contact with collar 45 by compression spring 46 disposed around control rod 32 internedgte the end of locking lever 44 and a further col- The operation of the control device is as follows. When a stud 30 comes into contact with one arm of bell crank lever 31 control rod 32 is displaced to the right and by means of contact blocks 37, 38 control rod 28 is similarly displaced to the right. By means of guide lever 27 cam follower 25 is brought into contact with a radial face of cam 26 and on rotation of said cam, slips into groove 48 of cam 26. Further rotation of cam shaft 2 brings about displacement of lever 22 in a backward direction and, by means of link 21, control lever 20, shaft 19, and forked levers 17, 18, causes frame 13 to slide in a backward direction through bar 10 and bring rollers 6, 7 into operative engagement with cam 5. Backward displacement of lever 22 permits rotation of locking lever 44 about pivot 49 under action of compression spring 46 thereby locking lever 22 in its backward position so long as control rod 32 is maintained displaced to the right by studs 30 on control chain 29.

The cams 4 and 5 impart different amplitudes of travel to bar l about a common central point and thus the cams 4 and 5 will coincide at the central point thereby enabling rollers 6, 7 to be simply and easily transferred from one cam to the other. The angular spacing of cam 26 and the cams 4 and 5 is such that lever 22 is displaced backwards substantially at the time when the rollers 6 and 7 are in the position corresponding to the central position of bar 10.

In operation in the first part of the hose, i. e. in the welt and in the leg, the rollers 6 and 7 are in operative engagement with the cam 4 and bring about movement of the slurcocks over the whole section. From the commencement of the high heel onwards the speed of the slurcock--and so also of the thread carriers-has to be decreased and the rollers 6, 7 transferred to operative engagement with cam in the manner previously described so that the amplitude of travel of the slurcocks and consequently their speed, is decreased. The speed of the machine and consequently the production speed, i

can therefore remain unaltered.

As, with this method of working, the slurcock is within the section during working of the stitches as soon as the amplitude of the slurcock travel is reduced, precautions should be taken to allow the catch bar to move rearwards during the working of the stitches, without the jack sinkers pushing the jacks up to the slurcock. This can be effected in a known manner such as by the arrangement shown in Fig. 2. In sinker head 61 beneath upper part 62 and head plate 63, are jack sinkers 64, 65, and dividing sinkers 66. Catch bar 67 of the machine, during the production of the stitches, moves the sinkers backwards and forwards. The jack sinkers 64, 65 are equipped with sinker butts of various heights. They are put in the sinker head in such a way that sinkers 65 with high butts work in the width of the foot, for example l0", while the remaining parts of the section are filled with jack sinkers 64 with low butts. When working the wide parts of the fabric the catch bar drops into the position shown by the full lines and thus moves all sinkers. As soon, however, as the slurcock remains within the section, the movement of the catch bar downwards is limited by any suitable controlled stop, so that it can only drop into the position shown by chain dotted lines. In this position only the dividing sinkers and the jack sinkers 65 with high butts and situated in the centre part of the section are moved during the production of the stitches, while the iack sinkers 24 with low butts in the outer portions of the section, are left in their forward position.

Another arrangement which can be employed if desired is shown in Fig. 3. This shows a front view of a catch bar plate 71 of the machine and the butts of jack sinkers 72. In this case all jack sinkers have butts of the same height but the front edge of the catch bar is dropped in the centre. Within the foot width 73 the catch bar has the normal shape. Outside the foot width, on the other hand, in the parts 74, 75, the lower edge of the catch bar is raised. When working the full width of fabric, the catch bar now drops so far, during the production of the stitches, that all the sinkers are drawn back. When working over the smaller width of fabric, however, the downwards movement of the catch bar is limited by any suitable controlled stop so that only the jack sinkers in the centre part 73 of the section and the dividing sinkers are drawn back, but the jack sinkers in the outer parts 74 and 75 remain in their forward position. In addition to the previously mentioned two possibilities a withdrawable slurcock can also be used if desired.

I claim:

l. ln a straight bar knitting machine such as the Cotton type, a draw mechanism for driving the slurcock bar and thread carrier from the cam shaft, including an auxiliary shaft, means to drive said auxiliary shaft from said cam shaft, draw cams of different amplitudes on said auxiliary shaft, transversely displaceable cam followers on said slurcock bar on opposite sides of said cams to engage said cams to reciprocate said slurcock bar, a transversely displaceable frame member carried on said slurcock bar to engage said cam followers selectively with one of said draw cams to impart a desired amplitude of movement to said slurcock bar, whereby the stroke of the draw mechanism and thereby the thread laying speed may be reduced during the knitting of narrower courses without reducing the number of courses knit per unit time.

2. In a straight bar knitting machine such as the Cotton type, a draw mechanism for driving the slurcock bar and thread carrier from the cam shaft, including an auxiliary shaft, means to drive said auxiliary shaft from said cam shaft, draw cams of different amplitudes on said auxiliary shaft, transversely displaceable cam followers on said slurcock bar on opposite sides of said cams to engage said cams to reciprocate said slurcock bar, a transversely displaceable frame member carried on said slurcock bar to displace said cam followers, lever elements to displace said frame member, a control cam on said cam shaft, a control cam follower to engage said control cam, link elements connecting said control cam with a control chain of the machine to bring said control cam follower into and out of engagement with said control cam and means to restrain movement of said control cam follower to cause said cam follower to engage selec tively with one of said draw cams to impart a desired amplitude of movement to said slurcock bar, whereby the stroke of the draw mechanism and thereby the thread laying speed may be reduced during the knitting of narrower courses without reducing the number of courses knit per unit time.

3. In a straight bar knitting machine such as the Cotton type, a draw mechanism for driving the slurcock bar and thread carrier, draw cams of different amplitudes, transversely displaceable cam followers on opposite sides of said cams to engage said cams, means connecting said cam followers and said slurcock bar for translating reciprocatory motion of said cam followers into reciprocatory motion of said slurcock bar, a transversely displaceable reciprocable element to engage said cam followers selectively with one of said draw cams to impart a desired amplitude to said slurcock bar.

4. ln a straight bar knitting machine, such as the Cotton type, a slurcock bar and thread carrier driving mechanism including at least two draw cams of different amplitudes, cam follower means to engage said cams, means connecting said cam follower means to said slurcock bar for translating reciprocatory motion of said cam follower means into reciprocatory motion of said slurcock bar, and means for shifting said cam follower means to engage selectively with one of said draw cams to impart a desired amplitude of movement to said slurcock bar, whereby the stroke of the draw mechanism and thereby the thread laying speed mav be reduced during the knitting of narrower courses without reducing the number of courses knit per unit time.

5. ln a straight bar knitting machine such as the Cotton type, a slurcock bar and thread carrier driving mechanism including an auxiliary shaft, draw cams of different amplitudes on said auxiliary shaft, cam follower means to engage said cams, means connecting said cam follower means to said slurcock bar for translating reciprocatory motion of said cam follower means into reciprocatory motion of said slurcock bar, and means for shifting said cam follower means to engage selectively with one of said draw cams to impart a desired amplitude of movement to said slurcock bar, whereby the stroke of the draw mechanism and thereby the thread laying speed may be reduced during the knitting of narrower courses without reducing the number of courses knit per unit time.

6. ln a straight bar knitting machine, such as the Cotton type, a slurcock bar and thread carrier driving mechanism including at least two draw cams of different amplitudes, cam follower means to engage said cams, means connecting said cam follower means to said slurcock bar for translating reciprocatory motion of said cam follower means into reciprocatory motion of said slurcock bar, means for shifting said cam follower means to engage selectively with one of said draw cams to impart a desired amplitude of movement to said slurcock bar, and means associated with the control chain of the machine for operating said shifting means, whereby the stroke of the draw mechansm and thereby the thread laying speed may be reduced during the knitting of narrower courses without reducing the number of courses knit per unit time.

7. ln a straight bar knitting machine such as the Cotton type a draw mechanism for driving the slurcock bar and thread carrier from the cam shaft, including an auxiliary shaft, means to drive said auxiliary shaft from said cam shaft, draw cams of different am litudes on said auxiliary shaft, a bar slidably mounte for reciprocation, transversely displaccable cam followers on said bar on opposite sides of said cams to engage said cams to recinrocate said bar, an element reciprocable in a direction transversely relatively to said bar and adapted to engage said cam followers to displace them transversely relatively to said bar to engage them selectively with one of said draw cams whereby to impart a desired amplitude of movement to said bar and thence to the slurcock bar and to reduce the thread speed during the knitting of portions of fabric of narrower width.

References Cited in the tile of this patent UNITED STATES PATENTS Graeber Mar. 4. 1930 Lieberknecht May 22, i934 Lieberknecht Jan. l0, 1939 FOREIGN PATENTS Great Britain June 18, 1943 Germany Aug. l0, 1934 Germany Get. 27, 1939 

